With an increased interest in cell-specific drug testing, diagnosis, and other assays, systems that allow for individual cell isolation, identification, and retrieval are becoming more desirable within the field of cellular analysis. Furthermore, with the onset of personalized medicine, low-cost, high fidelity cellular sorting and genetic sequencing systems are becoming highly desirable. However, conventional technologies for cell capture systems posses various shortcomings that prevent widespread adoption for cell-specific testing. For example, flow cytometry requires that the cell be simultaneously identified and sorted, and limits cell observation to the point at which the cell is sorted. Flow cytometry fails to allow for multiple analyses of the same cell within a single flow cytometry workflow, and does not permit arbitrary cell subpopulation sorting. In other examples, conventional microfluidic devices rely on cell-specific antibodies for cell selection, wherein the antibodies that are bound to the microfluidic device substrate selectively bind to cells expressing the desired antigen. Conventional microfluidic devices can also fail to allow for subsequent cell removal without cell damage, and only capture the cells expressing the specific antigen; non-expressing cells, which could also be desired, are not captured by these systems. Such loss of cell viability can preclude live-cell assays from being performed on sorted or isolated cells. Cellular filters can separate sample components based on size without significant cell damage, but suffer from clogging and do not allow for specific cell identification, isolation of individual cells, and retrieval of identified individual cells. Other technologies in this field are further limited in their ability to allow multiplex assays to be performed on individual cells, while minimizing sample preparation steps and overly expensive instrumentation.
In the field of single cell analysis, the isolation, identification and genetic analysis of rare cells, such as cancer stem cells, currently suffer limitations in accuracy, speed, and throughput. Furthermore, many systems do not maintain the viability and/or quality of living cells or biological materials extracted from cells, as typical methods for identification of cells during the isolation process necessitates fixation, staining, or an additional biochemical process at higher temperatures, which may damage the cell and/or its genetic material, in addition to slowing processing speed. Thus, there is a need in the cell sorting field to create new and useful systems and methods for isolating and analyzing cells, which are able to maximize viability of cells and their intracellular components, including biomolecules such as messenger RNA, for downstream analysis. Furthermore, cell isolation workflows that further include molecular indexing of biomolecules and processing of genetic transcripts can provide several benefits for improving throughput and accuracy for applications in cellular analysis, including massively parallel RNA sequencing for full-length mRNA, whole genomes and/or single-cell exomes. To date, there are no systems and/or methods that facilitate single cell isolation and DNA/RNA sequencing library construction on a single, unified device. The system and method described herein address these limitations by integrating functions such as single-cell capture, biomolecule labeling, fluid delivery, and temperature modulation, in order to enable more advanced biochemical processes to be performed on individual cells within the same array of wells used to capture the cells (e.g., reverse transcription, polymerase chain reaction, single cell genome (DNA/RNA) sequencing), thereby vastly improving capture efficiency for desired cells and increasing speed and analytical capabilities for single-cell experimental workflows.